Abstract
The complexity of vehicles increases every day with the introduction of new functionalities for greater safety, comfort and environment. With the introduction of multiplexed bus, the intuitive diagnosis disappears : for example, the cause of dysfunction of the air conditioning could be a component with no direct relationship with this system.
In addition to the classical approach consisting in reading ECUs fault codes, new technology are introduced in diagnostic tools, such as MBR (Model Based Reasoning) and CBR (Case Based Reasoning).
CBR works with cases, composed by a detailed description of a problem and its solution. The CBR technology allows to recover the nearest solution to a given problem between the old known cases.
Using a symptom approach, close to the description of the trouble seen by the driver, the mechanics finds again his human behaviour to solve a problem : Have I seen this trouble before ? What was the solution and can I use it to fix this new problem ?
CBR is a new way to introduce trouble not seen during the design of a vehicle, and to transmit on information. There is no need for each mechanics to lose time on a problem for which the solution is known. In fact, you ve just have to give the solution and the best way to find it.
The CBR application domain is not restricted to electric/electronic troubles, already covered by classic diagnostic methods. CBR has its place to introduce the world of communication into the diagnostic tool.